黄色荧光粉Sr3SiO5:Eu2+相转变机理简

高温固相法合成Sr3 SiO5：Eu2＋过程中，杂质相Sr2 SiO4：Eu2＋的存在会不同程度影响Sr3 SiO5：Eu2＋的光致发光性能及余辉性能。本文通过压片烧结和燃烧法两种方法制备Sr3 SiO5：Eu2＋，结合热重-差热分析和X射线衍射分析，研究了Sr3 SiO5：Eu2＋在合成过程中的相变化规律以及动力学过程。研究表明：原料与坩埚的接触处形成的界面以及原料在升温过程经过Sr2 SiO4：Eu2＋的合成温度区间是导致杂质相产生的主要原因。在升温过程中，当温度经过1200℃左右的温度区间时，由于原料与坩埚接触处可以看作是两组不同物质的分界面，Sr2 SiO4：Eu2＋的合成首先在该分界面处合成，而更多的原料需要扩散通过生成物层才能进一步反应；但随着温度的升高，原料随后进入Sr3 SiO5：Eu2＋的合成过程，从而导致了Sr2 SiO4：Eu2＋杂质相的生成。

Phase transformation mechanisms in the synthetic process of Sr3SiO5 ：Eu^2＋ yellow phosphors

Sr3 SiO5：Eu2＋yellow phosphors were synthesized through the high temperature solid state reaction method under a re-ductive atmosphere.Impurity phase Sr2 SiO4：Eu2＋acts as the phase and significantly affects the photoluminescence and afterglow properties of Sr3 SiO5：Eu2＋ yellow phosphors.In the synthetic process,the phase transformation process and kinetic process were investigated by DTA／TG,tabletting,combustion and XRD patterns.It is indicated that the thermal field between raw ma-terials and the crucible is responsible for the impurity phase.In the synthesis process,at around 1 200℃,the area where the raw materials are in contact with the crucible can be regarded as the interface of two different components,and thus,the synthesis of Sr2 SiO4：Eu2＋firstly occurred in the interface and generated product layer Sr2 SiO4：Eu2＋.Further reaction occurs when more raw materials diffuse through the interface.Finally,Sr3 SiO5：Eu2＋ yellow phosphors will be synthesized at higher temperatures,and the impurity phase was therefore formed.